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having poles set alternately all round a circular frame. from 5000 to 7000 if the driving power is proportionately Figs. 4 and 5 show how this is carried out. A cast-iron increased. The machine is now in operation at the ring having projecting iron pieces screwed into it is sur- Telegraph Construction and Maintenance Company's rounded by zig-zag conductors which carry into it the Works, East Greenwich. current from a separate exciter. These currents pass up A great deal has been said in certain quarters of late and down between the projecting cheeks, and excite about another new dynamo, the invention of Mr. those on both sides of them.
Ferranti, which, with one
those unscientific exagA still more recent, and still larger generator, is that de- gerations which cannot be too strongly condemned, was signed by Mr. J. E. H. Gordon, whose“ Physical Treatise pronounced to have an efficiency five times as great as on Electricity and Magnetism” is known to most of our that of existing dynamos. The construction of this mareaders. This machine, which is given in elevation in Fig. 6, chine has not yet been made known, but it is understood and in end-elevation in Fig. 7, is more than 9 feet in height, that it has no iron in the rotating armature. This is, and weighs 18 tons. It possesses several points of interest. however, no novelty in dynamos. It appears, also, that The rotating armature differs from those of the well-known Mr. Ferranti has invented an alternate current machine Gramme or Siemens' armatures, being in form a disc, almost identical with that of Sir William Thomson constructed of boiler-plate, upon which the coils are described above. carried. The machine, therefore, resembles in some Lastly, M. Gravier claims to have designed a form of respects the Siemens' alternate-current machine, though dynamo in which there are neither commutators nor there are notable points of difference, the most important separate exciters, but in which continuous currents of
electricity are produced in stationary coils by the passage near them of a rotating series of iron bars whose mag
netism is changed, during their passage, by the reaction of the cores of the stationary coils themselves. M. Gravier has also designed a machine in which a Gramme-ring is wound with iwo sets of coils, a primary and a secondary, each set having its own commutator on opposite ends of
the axis. A current from a separate exciting machine Fig. 7.-End Elevation and Section of Gordon's Dynamo.
passes into the primary coils of the ring by ore pair of being, that whereas in most dynamo-machines the in- brushes, and the secondary current is taken off by a ducing field-magnets are fixed, and the induced coils
second pair of brushes at the other commutator placed at rotating, in Mr. Gordon's new machine the rotating coils right angles to the first pair. We are not aware that any are those which act inductively upon the fixed coils practical machine thus constructed has yet been shown between which they revolve. The machine furnishes
in action. alternate currents, and therefore requires separate exciters.
It is certain that there is yet abundant room for great These exciters, two Bürgin machines, send currents which improvement in the construction of dynamo electric enter and leave the revolving armature by brushes press- machines. But the indı cements to improvement at the ing upon rings of phosphor bronze placed upon the axis present time are so great that rapid progress toward the at either side. There are 64 coils upon the rotating desired goal of perfect efficiency and simplicity of structure disc, and double that number upon the fixed frame
is more than assured. work. These 128 “taking-off” coils, the form of which is shown in Fig. 8, are alternately connected to two circuits, there being 32 groups in parallel arc, each
THE PROJECTION PRAXINOSCOPE parallel containing 4 coils in series ; thus
bringing the M. GA ingenious adaptation of the praxinoscope, under
GASTON TISSANDIER describes in La Nature total electromotive force to 105 volts when the machine is driven at 140 revolutions per minute. At this speed it the above name, by means of which the images are proactuates 1 300 Swan lamps, but is calculated to actuate ) jected on a screen, and are visible to a large assembly.
Our engraving will give an idea of the arrangement and subject are drawn and coloured on glass, and are conthe effect produced. By a modification of the “lampa. nected in a continuous band by means of any suitscope,” M. Reynaud, the inventor, obtains by means of able material. One of these fiexible bands is placed in an ordinary lamp, at once the projection of the scene or the wide crown of the praxinoscope, which is pierced background-by the object-glass which is seen at the side with openings corresponding to the phases of the subject. of the lantern-and of the subject, by another object. To understand the course of the luminous rays which go glass which is shown in front of and a little above the same to form the image, it is necessary to bear in mind the lantern. For this, the positions or phases which form a condensing lens which, placed near the flame of the lamp,
is not visible in the figure ; then a plane mirror inclined, middle of the background, where it then appears to 45°, which reflects the rays and causes them to traverse gambol. A hand-lever on the foot of the instrument the figures filling the openings of the crown. These rays, allows a moderate and regular rotation to be communireflected once more by the facets of the prism of mirrors, cated. This apparatus, with an ordinary moderator lamp, finally enter the object-glass, which transforms the verti- supplies well-lighted pictures and curious effects. It cal central image into a real image magnified on the enables us to obtain, with the greatest ease, animated screen. In making the two parts of the apparatus con- projections, without requiring any special source of light, verge slightly, the animated subject is brought into the l by simply utilising the lamp in daily use.
The President and Council of the Geological Society hold a
conversazione in the Socieiy's rooms on Wednesday, the 29th We take the following from the Times :—The council of the inst. Fellous of the Society who have objects of interest suitable Royal Society have awarded the medals in their gist for the for exhibition are asked bindly to lend them for the occasion. present year as follows: The Copley Medal to Prof. Cayley,
It is announced that General Pitt Rivers will be appointed F.R.S., for his researches in pure mathematics ; the Rumford Medal to Capt. Abney, F.R.S., for his photographic researches Inspector of Ancient Monuments under the recent Act. and his discovery of the method of photographing the less
We announced last week the death, at the age of sixty. refrangible part of the spectrum, especially the infra-red region ; six years, of Prof. Johannes Theodor Reinhardt, Inspector a royal medal to Prof. W. H. Flower, F.R.S., for his contribu- of the Zoological Museum of the University of Copentions to the morphology and classification of the mammalia and hagen. Prof. Reinhardt was a well-known zoologist, author to anthropology; and a royal medal to Lord Rayleigh, F.R.S., of an excellent memoir on the Birds of the Campos of for his papers in mathematical and experimental physics ; the Brazil, and of numerous papers in the scientific periodicals of Davy Medal (in duplicate) to D. Mendelejeff and Lothar Meyer Copenhagen, and will be regretted by many friends and correfor their discovery of the periodic relations of the atomic weights. spondents in this country. These medals will be presented at the anniversary meeting of At the sittirg of the Paris Academy of Sciences on November the society on St. Andrew's Day.
13, M. Faye read letters from the captain of the Niger, French
war steamer, on the comet, stating that it was seen at Buenos Prof. F. M. Balfour, was carried unanimously, and a letter exAyres, in the streets, on November 18, in close vicinity to the pre:sive of their feelings was directed to be sent to Mrs. Henry : un, and that the tail was seen for the first time on board the Sidgwick (Prof. Balfour's sister). The officers for the ensuing Niger on September 26. The expanse of the tail was then 28°, year were appointed as follows :-President, Mr. J. W. L. and its transversal dimension 26°. The quantity of light was so Glaisher, F.R.S. ; Vice-Presidents : Profs. Babington, Newton, great that when the end of the tail began to become visible the and Cayley; Treasurer, Dr. Pearson ; Secretaries : Mr. J. W. officers and sailors witnessing the phenomenon were quite unable Clark, Mr. Trotter, and Mr. W. M. Hicks; new Members of to understand the real nature of this splendid illumination. Council : Dr. Campion, Mr. E. Hill, and Mr. J. N. Langley. MR. B. J. HOPKINS, of Dalston, sends us a drawing of the
With regard to the recent sad suicide of a girl by leaping head of the comet, which he saw on November 8, 16h. 5om.
fron one of the towers of Nôtre Dame, Dr. Bronardeli's ex. Viewed with the naked eye, Mr. Hopkins states, the nucleus pre-sed view that asphyxiation in the rapid fall may have been
the cause of death, has given rise to some correspondence in La appeared equal to a second-magnitude star; the tail was dis
Nature. M. Bontemps points out that the depth of fall having tinctly visible, having a length of about 19°; it was straight for
been about 66 metres, the velocity acquired in the time (less than four-fifths its length; it then abruptly curved upwards and spread
four seconds) cannot have been so great as that sometimes itself out in the shape of a fan, with a breadth of 4°. It was
attained on railways, e.g. 33 metres per second on the line still brightest on the southern side. Observing at 17h. 3om. the
between Chalons and Paris, where the effect should be the same; nucleus-as seen with a 5-inch refractor—had the appearance of being double, there being two portions of equal brightness yet we never hear of asphyxiation of engine drivers and stokers. separated by a narrow space of less brightness, the whole being exploded, as unhappy persons may be led to choose suicide by
He considers it desirable that the idea in question should be surrounded by a circular nebulosity. The line joining the two
fall from a height, under the notion that they will die before bright portions of the nucleus formed an angle with the axis of the tail; and the tail immediately following the nucleus was
reaching the ground. Again, M. Gossin mentions that a few most clearly and sharply divided into two portions of unequal years ago a man threw himself from the top of the Column of brightness, the southern, as before mentioned, being by far the ! July, and fell on an awning which sheltered workmen at the most brilliant. The dark rift in the tail was not so conspicuous pedestal; he suffered only a few slight contusions. M. Remy
says he has often seen an Englishman leap from a height of as on the 5th inst.
31 metres (say 103 feet) into a deep river ; and he was shown in M. Tresca presented to the Academy of Sciences on 1852, in the island of Oahu, by missionaries, a native who had Monday the third part of his great work on
fallen from a verified height of more than 300 metres (say 1000 taken during the Paris Electrical Exhibition. It relates to the feet) His fall was broken near the end by a growth of ferns analysis of electric candles, and will be followed by a similar and other plants, and he ha i only a few wounds. Asked as to work on incandescent lights. M. Mascart sent a paper on mea- his sensations in falling, he said he only felt dazzled. sures taken with the registering electrometer in compliance with
Dr. SLUNIN has published in Russian a work—“Materials the wish expressed by Sir William Thomson to test the relations
for the Knowledge of Popular Medicine in Russia ”—which will of the state of the weather and the electrical properties of the
be received with interest, not only by medical men but also by air.
ethnographers. Dr. Slunin gives a detailed account of all At the same meeting M. Janssen read in the name of the plants and drugs used not only in Russian popular medicine ia Bureau des Longitudes a report on the observations which will be
the governments of Saratoff and Astrakhan, which he knows made during the total eclipse of the sun of May 6, 1883, which from many years' residence, but also in all Persian, Tartar, and will be observed in the Pacific Ocean.
He also read a paper
Central Asian medicines (with their Arabian names) that have on his work on solar spectroscopy, and on the observation come to his knowledge. His remarks on popular pharmacies of telluric rays.
Admiral Mouchez read a letter from M. and on the popular medical literature which goes as far back as Henry, who has been sent to the Pic-du-Midi to observe the the epoch of the flourishing times of Arabian civilisation are of forthcoming transit of Venus and determine the possibility of great interest. establishing an astronomical observatory on the top of the mountain.
The Catalogue of the Reference Department of the Derby
Free Library is of a handy size and excellent type. We are told The French Journal Officiel has published a decree of the it contains 60,0ɔo references to works upon the library shelves ; President establishing a council for the Observatory of Mentone. and, upon dipping into it, the minuteness of connection which We are informed that the contract for the construction and
will lead to a reference to publications of scarcely higher standerection of the Forth Bridge has been let to Sir Thomas Tan
ing than a newspaper, is imposing. We grieve to add, however, cred, Bart., Mr. J. H. Falkiner, and Mr. Joseph Phillips, Civil
that this holds good in both senses of the word. For looking
As Engineers and Contractors, of Westminster, and Messrs. Arrol
more closely we find most important references are absent. and Co. of the Dalmarnock Iron Works, Glasgow. Messrs.
a sample, eight references are given to the name of Garrick, but
neither is his life by Murphy or Davies quoted, nor is Tancred and Falkiner have already carried out about seventy miles of railway for Mr. Fowler, and are at present constructing the extraordinary explanation of this is found in the fact that
ence made to Boswell's “ Johnson," or Goldsmith's Poems; aud the new line to Southampton. Mr. Phillips has had a very wide
neither of these works is in the library! And this absence ot practical experience in bridge construction and erection, and Messrs. Arrol and Co. are contractors for the new Tay Bridge, carried out also with the most even-handed fairness to all sub
important works seems to be the rule rather than the exception, so the works are in good hands. The contract sum is 1,600,000l., jects. Looking through the letter B as a sample, we find no which is within 5000l. of the engineer's parliainentary estimate. The tenders received ranged from 1,485,000l. to 2,300,000l.,
works of Babbage, Back, Barbauld, Barry (Sir C.), Baxter, Beale, most of the leading firms being represented.
Baden Powell, Brewster, Barrow (Isaac or Sir Jno.), Bayne,
Beckmann, Blackie, Blackstone, Borrow, Boswell, Bowring, At the annual general meeting of the Cambridge Philosophical | Bridgewater Treatises, Browning (Mrs.), Buckmaster, Brixton. Society, a resolution recording the deep regret of the Society at Butler (Bp.), or Butler (S.). Among Dictionaries neither the lamentable event which deprived them of their late president, the Penny nor the English Cyclopædia is to be found.
Nor is it that a selection of certain writers has been MR. MURRAY has issued a cheap edition of Dr. Blaikie's made, for numerous authors of many well-known works are “Life of David Livingstone." only credited with one or two in the Derby Library Cata
The additions to the Zoological Society's Gardens during the logue. The letter B is not a specially unfortunate one.
past week include two Macaque Monkeys (Macacus cynomolgus Ancient Geography refers only to Nature and the Quarterly
88) from India, presented respectively by Mr. J.'Knight and Review (one reference each). Gladstone and Hugh Miller are
Mrs. Snell; a Sooty Mangabey (Cercocebus fuliginosus 8 ) from eqnally unknown. Less than a column contains all the references
West Africa, presented by Lady Stafford; two Globose Cura ;to Geography, while Geology has nine columns allotted to it.
sows (Crax globicera 8 %) from British Honduras, presented Unler Astronomy the inquirer is referred to numerous papers by Mr. R. W. Ryass ; a Buzzard
) from where notices may be found of each of the planets and of many
Demerara, presented by Mr. G. H. Hawtayne, C.M.Z.S. ; of the planetoids, but only fifteen works on Astronomy are
three Common Chameleons (Chameleon vulgaris) from Egypt, catalogued. There is no work at all upon the Moon! More
presented by Mr. W. J. Ford ; a Hawk's-billed Turtle (Chelone over, the references to works which are in tbis library are made imbricata) from West Indies, presented by Mr. W. Cross ; a with no discretion. “ Barbarossa” does not refer the reader to
Pig-tailed Monkey (Macacus nemestrinus 8 ) from Java, a Black Gibbon; “Borgia" only refers him to one article—on Lucrezia
Wallaby (Halmaturus ualabatus ®) from New South Wales, a in the Nineteenth Century! The spelling is not only unscholarly,
Greek Land Tortoise (Testudo græca), South European, depo. but the correcting of proofs is careless. It were endless to point sited; an American Bison (Bison americanus 8 ) from North out the blunders everywhere ; we need only refer to the name of
America, a Capybara (Hydrochærus capybara 9 ) from South Prof. Haeckel, spelt in four different ways upon pp. 41, 42 only! | America, two Eastern Goldfinches (Carduelis orientalis) from If some little town struggling against the smallness of the
Afghanistan, two Brent Geese (Bernicla brenta), a Red-throated id. rate wishes to draw as much as possible from its Free
Diver (Colymbus septentrionalis), British, purchased ; three Library with its motley collection of books contributed from Capybaras (Hydrochærus capybara 8 8 %), a Bluish Finch various quarters, we can strongly recommend the system upon (Spermophile cærulescens) from South America, received in which this catalogue is drawn up. But that a place of the size
exchange. and importance of Derby, whose rate also has been so helped by the munificence of Mr. Bass and others, should think it worth while to print and distribute a catalogue, displaying a knowledge
GEOGRAPHICAL NOTES and a collection of books in this rudimentary state, is beyond Ar the opening meeting of the Geographical Society on our comprehension.
Monday Mr. A. R. Colquhoun' gave an account of his recent The population of Cascia (Italy) is being constantly disturbed
adventurous journey, in company with the late Mr. Wahab,
from Canton through Yunnan to Bhamo. Mr. Colquhoun's by repeated subterranean shocks.
object was mainly to discover trade-routes between Burmah and A VOLCANIC eruption is reported to have taken place from a
China, but he collected some interesting information on Further mountain in the Caucasus, which has not shown any volcanic
Yunnan, parts of which have not before been visited by Euro.
pean travellers. Mr. Colquhoun describes Yünnan, which is phenomena during historic times. It is the Karabetow mountain,
the most westerly of the eighteen provinces of China, as a great Dear Temrink, in the government of Jekaterinodar (Caucasia). uneven plateau, of which the main ranges trend north and The subterranean noi e was heard 4 versts away, the lava flowed south ; tho.e in the north reaching an elevation of from twelve for a distance of half a verst, and a large crater was formed.
to seventeen thousand feet, while in the south they sink to seven
or eight thousand feet. In the south, and especially in the News from Belgrade states that some railway workmen have south-west, there are many wide fertile plains and valleys, some discovered a nearly perfect mammoth skeleton. It is being with large lakes in them. These plains are very rich and thickly photographed on the spot, and will be handed over to the populated, the number of towns and villages and the comfortNational Museum at Belgrade.
able appearance of the peasantry being very remarkable. Fruits
of all kinds-pears, peaches, chestnuts, and even grapes-are A NATURAL intermittent spring has recently formed in found in abundance, while roses, rhododendrons, and camelias the Jachère (Hameau de l'Argentière, Hautes Alpes). At of several varieties grow untended on the hill-sides. Minerals rezular intervals of five and seven minutes it yields 10 litres of
are found in great quantities. The travellers constantly passed
caravans laden with silver, lead, copper, and tinin inwater each time. It is very remarkable that the first time it consists
gots; and gold is beaten out into leaf in Tali, and sent of lukewarm and colourless water, but the second of cold but
in large quantities to Burma, Coal, iron, silver, tin, and wide-red water. MM. Chester and Hadley are now studying copper mines were frequently passed. Mr. Colquhoun alsə the phenomenon.
found that the celebrated Puerh tea, the most fancied in
China, is not really a Chinese tea at all, but is grown M. J. OLLER, the proprietor of the St. Germain racing esta in the Shan district of I-bang, some five days south of blishment, is preparing to organise night races. He intends to Puerh, the nearest prefectural town. In the south the temperabuild a central lighthouse, of which the rays wil be directed on
ture is moderate, and the rains by no means excessive; but the the contending horses, so that spectators sitting in the centre
farther north the travellers went, the more sparse became the may follow the proceedings with as much accuracy as in
population, and the more sterile the country, until in the ex
treme north the bills were enveloped in al nost perpetual fogs, open day.
rain , and mists, and were practically uninhabitable. The people At the annual meeting for the distribution of prizes in Mason
them-elves are mostly the old aboriginal tribes--Lolo, Pai, and
Maio—the Chinese being mostly of the official class, and found College, Birmingham, Prof. Tilden gave a sensible and interest.
only in the towns. These aborigines have a much more distinct ing address on Technical Education, which has been published physiognomy than the bullet-headed Celestial, and are remarkin a separate form.
able for their frank and genial hospitality. The women do not The Captaia-General of the Philippines reports another de
crush their feet, and they adopt a picturesque dress not unlike
that worn of old by Tyrolese and Swiss maidens. They have structive hurricane on November 5, and it is worthy of remark a novel way of making marriage engagements. On New Year's that since the frevious hurricane, a few weeks ago, the cholera, Day the unmarried people range themselves, according to sex, which had been very bad, has nearly disappeared from Manilı.
on either side of a narrow gully. The ladies in turn toss a Messrs. SONNENSCHEIN AND Co. announce the forthcoming happy man.
coloured ball to the other side, and whoever catches it is the
It is said they are so skilful in throwing the ball publication of Dr. Coppinger's Notes of the four years' voyage that the favoured man is always sure to catch it ; which is reasfrom which the Alert has recently returned.
suring. As in Marco Polo's days, the couvade still prevails in
some parts. When a child is born, the husband goes to bed for they, in short, been formed by unequal subsidences of the thirty days, and the wife looks after the work. At the conclu- ground? Some considerable inland seas, as for example the sion of the paper, Lord Northbrook and Col. Yule paid a well Dead Sea, and doubtless many larger and smaller sheets of deserved tribute to the late Capt. Gill, Prof. Palmer, and Lieut. water, owe their origin to local movements of this kind. But it Charrington. Capt. Gill, our readers may remember, had him- | is incredible that all
the numerous lakes and lakelets of Northern self done some first-rate work on the South-East Chinese Alpine regions could have originated in this way.
In many frontier, and described it in his “River of Golden Sand ;" cases these lakes are so abundant that it is hard to say of some while Prof. Palmer's loss as an Arabic scholar is almost countries, such as Finland, and large parts of Sweden, and even irretrievable.
of our own islands, whether it is land or water that predominSAMOYEDES report to Archangel that they have recently seen,
ates. If all these numerous and closely aggregated rock-basins south of Waigatz Island, the wreck of a large vessel crushed in represent so many local subsidences, then the hard rocks in the ice. If the statement be true, and if we remember their which most of them appear must have been at the time of their never-credited story of the unfortunate Jeannette, it is more
formation in a condition hardly less yielding than dough or putty. than probable that the vessel is either the Danish exploring It was suggested that the lakes of the Alps and other hilly vessel thc Dijmphna, with Lieut. Hovgaard's expedition, or the regions might have been caused, not by local sinkings confined Norwegian steamer Warna with the Dutch meteorological expe to the valleys themselves, but by a general depression of the dition, bound for Port Dickson, both of which in September last central high-grounds and water-sheds. The subsidence of the froze in in the Kara Sea, from which place the ice may subse
central mountains would of course entail depression in the upper quently have carried the unfortunate vessel to where she now is reaches of the mountain-valleys, and in this way the inclination stated to be. The last intelligence received from Lieut. Hovgaard of those valleys would be reversed-each being converted into was dated September 22, and addressed to Herr Aug. Gamil, of an elongated rock-basin. But a little consideration showed that Copenhagen, the principal promoter of the expedition, from before the lakes of such a region as the Alps could have been which it appears that all was then well with both vessels, but produced in this manner, those mountains must have been some that the Dijmphna was, when caught in the ice, some consider 15,000 feet higher than at present. Oe to put it the other way, able distance from shore, in fact in a spot where the whole force in order to obliterate the Alpine lakes and restore the slopes of of the polar ice, when in drist, would strike her, Herr Aug. the valleys to what, if this hypothesis were true, must have been Gamil having telegraphed to the Russian Admiralty for any con their original inclination, the Alps would need to be pushed up firmation of the above report, has received a reply that no official until they attained twice their present elevation. Now, we are information on the subject has been received at St. Petersburg ; hardly prepared to adapit that the Swiss mountains were 30,000 but that nevertheless instructions would be at once given to the feet high before the glacial period. If our Alpine and Northern officials on the north coast to scour the same, and gather further
lake-basins cannot be attributed tu movements of depression, particulars. A search party is also being contemplatid in still le-s can they be accounted for by any system of fractures ; Copenhagen, which will, if decided on, be led by M. Larsen, a --they lie neither in gaping cracks nor on the down-throw sides Dane, who accompanied the American expedition in search of of dislocations. In a word, a study of the structure, inclination, the crew of the Jeannette, as the special artist of the Illustrated and distribution of the rock-masses in which our lake-basins London News.
appear throw. no light upon the origin of those hollows. We The German Government has raised the fund for the scientific
probably find in many cases that the position and form of a basin
have been inflaenced in some way by the character of the rocks exploration of Central Africa and other countries, which in
in which it lies—but we detect no evidence in the rock-masses 1882-83 was fixed at 75,000 marks (3750/.) to 100,000 marks
themselves to account for its production. It is not necessary, (5000l.) for the financial year 1883-84.
however, that I should on this occasion mention each and every
cause which has been suggested for the origin of rock-bound THE AIMS AND METHOD OF GEOLOGICAL
hollows. Some of these suggestions are unquestionably well
founded. For example, there can be no doubt that certain lakes INQUIRY1
have been produced by the sudden damming-up of a valley in II.
consequence of a fall of rock from adjoining slopes or cliffs ; It will be observed that the results obtained by geologists others, again, occupy holes cau-ed by the faling in of the roofs could not have been arrived at had they confined themselves
of caves and subterranean tunnels ; while yet others have been solely 10 the detection of resemblances and correspondences formed by a current of lava flɔwing across a valley and thus between the phenomena of the present and the past.
The ponding back its stream, just as many a temporary sheet of natural forces have always been the same in kind, if not in
water has been brou zht into existence in a similar way by the degree, and we can often watch the gradual development by have doubtless originated again and again, but the causes just
abnormal advance of a glacier. In these and other ways lahes their means of products which more or less closely resemble the rocks of our sections. But experimental evidence of this kind
referred to are all more or less exceptional, and manifestly intakes us only a short way, and we are sooner or later confronted
capable of producing the phenomena so conspicuous in the lakeby appearances, which are not reproduced by nature before our regions of Britain, Scandinavia, and the Alps. eyes. As another example of this I shall adduce one wbich,
Ramsay, to whom the varied phenomena of glacier-regions although it has far-reaching issues, has yet the merit of being had been long familiar, was struck by the remarkable fact that readily comprehended without much prelim nary geological | while they are comparatively rare in regions further south and
freshwater lakes predominate in Northern and Alpine countries, knowledge. It is moreover instructive as showing how the imaginative faculty works in a mind trained to clear and steady lakes in Finland finds no counterpart in the low grounds of
outside of mountainous districts, The great development of observation of nature. The fact that a large proportion of the
southern latitudes. lakes of the world rest in rocky hollows or basins had been long
It is in regions where glacial action formerly known before it occurred to any one to ask how such rocky prevailed that rock-basins are most numerous, and this suggested hollows had come into existence. The question was first asked
to Ramsay that in some way or other the lakes of the Alps and and the answer given by Prof. (now Sir) A. C. Ramsay. He
the North were connected with glaciation. The final solution of had pondered over the problem for years before its solution
the problem flashed upon him while he was studying the glacial dawned upon him. None of the ordinary agents of geological features of Switzerland. His scientific imagination enabled him change seemed capable of producing the phenomena. The
to reproduce in his own mind the aspect presented by the Alps most common of all denuding agents-water-certainly could during the glacial period, when the great mountain-valleys were not do so, for although it may dig long and deep trenches
choked with glacier-ice, which flowed out upon the low grounds through rocks, water could not scoop out a basin like that
of Germany, France, and Northern Italy, so as to cover all the occupied by Loch Lomond, or any of our Highland lakes. The
sites of the present lakes. He saw that under such conditions tendency of water is, on the contrary, to silt up and to drain
enormous erosion must have been effected by the ice, by means such hollows, by deepening the points of exit at their lower ends.
of the rocky rubbish which it dragged on underneath, and that Did the hollows in question occupy areas of depression-had this erosion, other things being equal, would be most intense
where the ice was thickest and the ground over wbich it The Inaugural Lecture at the opening of the Class of Geology and
advanced had the gentlest inclination. Such conditions, he Mineralogy in the University of Edinburgh, October 27, 1882, by james Geikie, LL.D., F.R.S. L. and E., Regius Professor of Geology and inferred, would be met with somewhere in the lower course of a Mineralogy in the University. Continued from p. 46.
valley between the steeper descent of its upper reaches and the